1. Combine the garlic, cayenne pepper, lime and beer or wine. Add the fish and let stand for 15 min.2. Heat the oil in a wok or large frying pan. Add the onion and peppers and cook for 4-5 min. or until they start to blacken in color.3. Add the fish and liquid and cook for 3-4 min.4. Serve with warmed fajitas accompanied by iceberg lettuce, sour cream, guacamole and salsa.